1. Field of the Invention
The present invention relates to a piezoelectric transducer using a piezoelectric element, and more particularly to an electrophoretic ink display apparatus using a piezoelectric transducer.
2. Description of the Related Art
The technology noted in Japanese Patent Laid-open Publication No.(Hei)8-125247 and Japanese Patent Laid-open Publication No.(Hei)9-162456 relates to conventional piezoelectric transducers. The embodiments therein are different, but both include technology using bulk piezoelectric ceramics.
Meanwhile, the paper in SID 98 Digest pp. 1131 to 1134 makes note of conventional electrophoretic ink display apparatuses. The constitution of a segment type display body using electrophoretic ink is disclosed in this paper.
In this electrophoretic ink display apparatus, each segment of the display apparatus is constituted of a plurality of microcapsules using electrophoresis. This is so that the color of a segment changes when voltage is applied to that segment.
However, the abovementioned background art has the following problems.
In the piezoelectric transducers noted in Japanese Patent Laid-open Publication No.(Hei)8-125247 and Japanese Patent Laid-open Publication No.(Hei)9-162456, bulk piezoelectric ceramics are used although the embodiments are different, as discussed above. It is difficult to miniaturize a piezoelectric transducer wherein bulk piezoelectric ceramics are used. For example, the piezoelectric transducer in Japanese Patent Laid-open Publication No. 9-162456 is 40 mm×10 mm×1.5 mm.
Also, while the constitution of a display body using piezoelectric ink is disclosed in SID 98 Digest pp. 1131 to 1134, methods for disposing a large number of these display elements at a high density and methods for driving electrophoretic ink display elements disposed at a high density are not proposed.